Last reviewed 2026-05-14 · How we verify

Gemzar (Gemcitabine Hydrochloride)

Gemcitabine kills cells during DNA synthesis and blocks G1/S-phase progression.

Gemcitabine is a nucleoside metabolic inhibitor approved for multiple solid tumors including ovarian, breast, lung, and pancreatic cancers, used as monotherapy or in combination regimens. The drug demonstrates linear pharmacokinetics with clearance significantly affected by age and sex, requiring dose consideration in geriatric and female patients. Primary safety concern is hypersensitivity reactions including anaphylaxis in susceptible patients. Clinical utility is established across multiple cancer types with well-characterized metabolism and renal excretion.

At a glance

Mechanism of action

Gemcitabine is metabolized by nucleoside kinases to diphosphate (dFdCDP) and triphosphate (dFdCTP) nucleosides. The diphosphate form inhibits ribonucleotide reductase, reducing deoxynucleotide concentrations including dCTP, which enhances incorporation of gemcitabine triphosphate into DNA (self-potentiation). The triphosphate competes with dCTP for DNA incorporation. After gemcitabine nucleotide incorporation into DNA, only one additional nucleotide is added to growing DNA strands, eventually initiating apoptotic cell death.

Approved indications

• Adenocarcinoma of pancreas
• Malignant tumor of ovary
• Metastatic Breast Carcinoma
• Non-small cell lung cancer

Common side effects

• Fatigue
• Nausea
• Anemia
• Constipation
• Diarrhea
• Anorexia
• Vomiting
• Neutrophil count decreased
• Platelet count decreased
• Neutrophils
• Dyspnea
• Hemoglobin

Key clinical trials

• Testing the Addition of an Anti-cancer Drug, BAY 1895344, to the Usual Chemotherapy Treatment (Cisplatin, or Cisplatin and Gemcitabine) for Advanced Solid Tumors With Emphasis on Urothelial Cancer (PHASE1)
• Durvalumab in Combination With Chemotherapy in Treating Patients With Advanced Solid Tumors, DURVA+ Trial (PHASE2)
• Novel Combination Therapy in the Treatment of Relapsed and Refractory Aggressive B-Cell Lymphoma (PHASE2)
• Study BT8009-230 in Participants With Locally Advanced or Metastatic Urothelial Cancer (Duravelo-2) (PHASE2,PHASE3)
• Reduced-dose Carboplatin-doublet-chemotherapy + Cemiplimab vs Cemiplimab Monotherapy in Treatment Naive Older and Frail Patients With Metastatic NSCLC With PD-L1 <50% (PHASE2)
• A Study of Sacituzumab Tirumotecan (Sac-TMT, MK-2870) as Monotherapy and in Combination With Pembrolizumab (MK-3475) in Participants With Triple-Negative Breast Cancer (MK-2870-011/TroFuse-011) (PHASE3)
• Testing the Addition of an Anti-cancer Drug, Pembrolizumab, to the Usual Intravesical Chemotherapy Treatment (Gemcitabine) for the Treatment of BCG-Unresponsive Non-muscle Invasive Bladder Cancer (PHASE2)
• A Study of Zilovertamab Vedotin (MK-2140) in Combination With Standard of Care in Participants With Relapsed or Refractory Diffuse Large B-Cell Lymphoma (rrDLBCL) (MK-2140-003) (PHASE2,PHASE3)

Patents

Primary sources

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Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

• Gemzar CI brief — competitive landscape report
• Gemzar updates RSS · CI watch RSS
• Accord Hlthcare portfolio CI